let nam: string = "好学生";
nam = "66666";
const na: string = "好学生"
let decl: number = 6;
decl = 6;
const dec: number = 7;
let hex: number = 0xf00d;
list = [2, 2, 2];
const ob: object = { "2,7": 3 }
const object: object = { "3,": 5, 'v': 4 }
